The prior art has prepared perfluorinated tertiary amines by electrolysis (note, e.g. U.S. Pat. No. 2,616,927). Only saturated perfluorinated tertiary amines can be prepared by such electrolytic route. Furthermore, the saturated perfluorinated tertiary amines prepared by the electrolytic method contain isomers, as during electrolysis normal chains partially isomerize to branched chains. Thus, it is difficult to obtain pure components using the electrolytic method without also utilizing tedious purification processes.
U.S. Pat. No. 2,859,245 discloses the preparation of organic fluorine compounds by reacting certain organic compounds, including carboxylic acid amides, with SF.sub.4, preferably with the use of hydrogen fluoride as catalyst. Example 18 involves the reduction of N,N-dimethylbenzamide to .alpha.-.alpha.-difluorobenzyldimethylamine in low yield. In J. Am. Chem. Sec., 82 543-551, 548 (1960), the patentee and others state that the reaction could not be reproduced consistently, with the suggestion that the reaction of an amide with SF.sub.4 to cleave the carbonyl-nitrogen bond is catalyzed by trace amounts of HF. The prior art has prepared perfluorinated tertiary amines using other processes, with, e.g. (R.sub.f).sub.2 NF used as an intermediate. Note, e.g. Banks et al., J. C. S. Perkin I, 1098 (1972). These routes do not appear to be feasible for commercial production, due to low yields and broad distributions of products obtained.
Other papers of interest as background to the present invention are J. Am. Chem. Soc., 87, 4338 (1965); J. Am. Chem. Soc., 80, 3604 (1958); J. Am. Chem. Soc., 84, 2105 (1962); and J. Chem. Sec. (C), 2920 (1971).